Clamp type carrier bar



Sept. 1 942- j A 3' M .d wssg T/6AM INVENTOR Patented Sept. 15, 1942 UNITED STATES PATENT OFFICE CLAMP TYPE CARRIERBAR Jaines' Pl Reagan, Los Angela-s, cam.

Application September 16, 1941, Serial No 411,043

Claims.-

invcnt-ion relates to aclamp for reciprm eating rods and has particular reference to a clamp type carrier bar which finds particular utility when employed to effect a driving conriec between the polished rod arid the horsehad sling of an oil well pumping installation.

The ground surface equipment which is at present employed in oil well pumping installations includesan oscillating walking beam,- from one end of which depends a pair ofhorsehead sling cables or rods, the lower ends of these rods or -cables being pivotally attached to the polished rod of the pump, For makingsuch pivotal connection, two different types of connectors have been commonly employed, one of these being a carrier bar having t-runnions at either end to engage the horsehead cables or rods and having a; hole through the bar through which the polished rod loosely projected, necessitating the use of a separate grip or clamp to be disposed above the carrier bar to rest upon and transmit the load to the carrier bar; This type requires that the grip and all other devices associated with the polished rod above the carrier must be removed in order to slide the carrier bar on of the upper end of the rodwhenever the carrier bar is to be removed and this necessitatesthe use of clamps or Wedges to support the polished rod during such removal;

The other type combines the tunctions of a grip and carrier bar by employing a carrier bar body with trunnions at each end and a vertical recess approximately midway therebetween to receive and partially surround the polished rod and in which the polished rod is frictionally held by clamping plate bolted to the carrier bar body across the open face of the recess In this type, however, the horizontal axis through the trunn-ions is considerably offset from the vertical axis of the polished "rod imposing bending forces upon the polished rod during all of the pumping operations;

Also the more modern of the standard pumping rigs employ a Samsompost (the upright which supports the oscillating walking beam), which is materially shorter than the posts which had previously been used in the older rigs This disposes the lower end of the horsehead sling nearer the stuifing box and thus materially limits the length of stroke which can be used employing the old types of carrier bars and grips because of the great vertical distances along the polished rod which are occupied by these old devices.

It is thereforean object of my invention to provide a combined polished rod grip and trunnion which will overcome the disadvantages of the previous devices in that my new grip combines in a single device both the polished rod grip and the trunnion connections for the horsehead cables of rods but having the grip portion thereof so designed as to require but a minimum length of rod gripping surfacepermitting the grip to be so constructed as to occupy a minimum of length along the rod.

Another object of my invention is to provide a polished rod grip of the character described in which the combined grip and trunnions are split along a central longitudinal vertical plane to divide the grip into two identical comp1ementary halves which may be disposed one on each side of the polished rod and clamped together whereby the grip may be readily disassembled for removal and replacement.

Another object of my invention is to provide a polished rod grip made in two identical halves from end to end, each of which includes onehalf of each of the trunnions, the meeting faces of the two halves being provided with identical polished rod receiving recesses or grooves whereby when the two halves are assembled together the horizontal axis through the trunnion is directly aligned with the vertical axis of the polished rod gripped between the members to eliminate bending stresses in the polished rod as the rod is supported and operated by the pumping mechani'smi Another object of my invention is to provide a construction of the character described in which the two identical halves are assembled together H and held in clamped relationby means of two bolts, one on each side of the polished rod and the heads of the two bolts projecting one on each sideof the grip whereby relatively large clamping bolts may be employed disposed in close re lation to the polished rod for applying the clamping forces in close relation to the axis of the polished rod and whereby access to the heads of each of the bolts may be had without inter ference from the head of the adjacent bolt.

Other objects and advantages of my invention will be apparent from a study of the following specifications, read in connection with the accompanying drawing wherein Fig. 1 is a perspective view illustrating the preferred embodiment of my invention and the manner in which the same is employed in oil well pumping installations;

Fig. 2 is a plan view of the device illustrated in Fig. 1; and

Fig. 3 is a longitudinal sectional view taken substantially along the line IIII1I of Fig. 1.

Referring to the drawing, I have illustrated in Fig. 1 a fragmentary portion of a typical oil well pumping installation, which includes a polished rod I to which is attached a clamp type carrier bar 2 forming the subject of the present invention. The polished rod I constitutes the upper one of a string of sucker rods which is extended from the ground surface downwardly through the well bore to a reciprocating pump plunger situated deep within the well bore. The pump plunger is reciprocated to effect a pumping of oil from the well by reciprocating polished rod I and this polished rod is therefore connected to an oscillating walking beam, not shown, by means of a horsehead construction which includes a pair of horsehead sling cables 3 and 4 terminating in eye members 5 and 6, respectively. The eye members are adapted to receive trunnions I and 8 which are preferably formed integrally with the carrier bar 2 and so serve to provide a driving interconnection between the walking beam and the polished rod I.

In accordance with the preferred embodiment of my invention, the clamp type carrier bar 2 is preferably formed by a pair of complementary members or halves 9 and III which are disposed in abutting relation to each other and which are separable along a longitudinal plane disposed between adjacently positioned meeting faces II and I2. Members 9 and II] are preferably identical and each includes a central enlarged body portion I3 carrying integrally formed trunnion portions I4 and I5, which portions are of semicylindrical form and extend axially outward from the body portion I3 in opposite directions. The plane surface portion of the semi-cylindrical form defined by the trunnion portions I4 and I5 preferably constitutes a continuation of the meeting faces II and I2.

When the device is assembled in the manner illustrated in Fig. 3, the semi-cylindrical portions I4 and I5 of each of the members 9 and I0 coact to define the two previously mentioned cylindrical trunnions I and 8. These trunnions are preferably pierced by laterally extending apertures I6 and I1 adapted to receive removable keepers I8 and I9 employed for the purpose of preventing the eye members from moving outwardly and ofr" of the ends of the trunnions I and 8. Each of the meeting faces II and I2 is preferably provided with grooves and 2| of arcuate cross section, which together define a channel for receiving the polished rod I. The polished rod I may be clamped in the channel defined by the grooves 20 and 2| by means of a pair of clamping bolts 22 and 23 which are disposed on opposite sides of the grooves 29 and 2| and preferably closely adjacent thereto, and which are extended through the body portions I3 in a direction transverse to the meeting faces II and I2 and also transverse to the length of the polished rod I.

As is clearly shown in Fig. 3, the bolt 22, for example, is preferably passed through a clearance hole 24 provided in one of the body portions I3 and threadedly engaged in a threaded opening 25 provided in the other body portion. When the device is assembled, the two parts 9 and III are preferably reversed, as is illustrated in Fig. 3, so that the bolts 22 and 23 are extended through the device in opposite directions, thus disposing the heads of the bolts on opposite sides of the device. By so disposing the bolts 22 and. 23 each of the bolt heads can be manipulated with a wrench without interference from the other of the bolts and the two bolts are thus permitted to be disposed in much closer relation to the polished rod than would otherwise be possible. Furthermore, by disposing the parts in the manner described, I am enabled to make the complementary members 9 and I0 identical.

The grooves 29 and 2| preferably have a depth which is slightly less than the radius of curvature of the arcuate cross section of the grooves and furthermore the meeting faces II and I2 are preferably slightly concave outwards. This may be accomplished by forming the faces II and I2 as curved surfaces or alternatively as illustrated in Fig. 3, the portions of the faces I I and I2 associated with the body portion I3 may be formed as plane faces whereas the extensions of the meeting faces associated with the trunnion portions I4 and I5 may be formed as plane surfaces disposed at a slight angle to the plane of the other surfaces. Thus when the device is assembled in the manner illustrated in Fig. 3, the meeting faces II and I2 first engage at the extremities of the trunnions I and 8. The depth of the grooves 29 and 2| is preferably so adjusted that concurrently with the abutting of the faces at the tips of the trunnions the bottoms of the grooves engage the polished rod Great clamping pressures may thus be exerted on the polished rod by tightening the bolts 22 and 23, since the body members I3 are permitted additional movement toward each other through the springing of the trunnion portions I4 and I5, which springing is permitted by the slight spaced separation of the inwardly positioned portions of the meeting faces II and I2.

It will thus be seen that I have provided a clamp type carrier bar in which the vertical forces applied to the carrier bar are always in direct central alignment with the axis of the polished rod gripped between the members, avoiding any bending moment in the polished rod at the point of attachment of the carrier bar.

It will also be apparent that by forming the members as identical complementary halves and disposing the bolts to project one from one side and the other from the other side of the clamp, relatively large diameter bolts may be employed disposed extremely close to the centers of the polished rod. In actual tests such clamping forces exerted through two 1 /;th inch bolts are so great that a load of more than 53,000 pounds is required before any slippage occurs between the carrier bar and the polished rod.

It will also be noted that by forming the separable members 9 and I9 identical, the cost of producing the device is reduced.

I have found that the device may be rapidly and inexpensively manufactured by a casting process, the only machining which is required being the reaming of the clearance holes 24 and the tapping of the threaded holes 25. It may occasionally be desirable or necessary to machine the grooves 20 and 2|.

While I have shown and described the preferred embodiment of my invention, I do not desire to be limited to any of the details of construction shown or described therein, except as defined in the appended claims.

I claim;

1. In a carrier bar for polished rods, a body member having integrally formed cylindrical trunnion members extending axially outward from said body member in opposite directions to be received in the eye members of a horsehead sling, said trunnion members each having an aperture for receiving a keeper to secure said eye members, said body member being formed as complementary halves separable along an axial planepassing between meeting faces defined by each of said halves, said meeting faces each being slightly concave outwardly, each of said halves having a groove of arcuate cross section extended along said meeting faces transversely of the axis of said body member to define a channel for receiving said polished rod, said grooves each having a depth slightly less than the radius of said arcuate cross section, and a pair of clamping bolts interengaging said halves, said bolts being disposed on opposite sides of said grooves and closely adjacent thereto. 7

2. In a carrier bar for polished rods, a body member having integrally formed cylindrical trunnion members extending axially outward from said body member in opposite directions, said body member being formed as complementary halves separable along an axial plane passing between meeting faces defined by each of said halves, each of said halves having a groove of arcuate cross section extended along said meeting faces transversely of the axis of said body member to define a channel for receiving said polished rod, said grooves each having a depth slightly less than the radius of said arcuate cross section, and a pair of clamping bolts interengaging said halves, said bolts being disposed on opposite sides of said grooves and closely adjacent thereto.

3. In a carrier bar for polished rods, a body member having integrally formed cylindrical trunnion members extending axially outward from said body member in opposite directions, said body member being formed as complementary halves separable along an axial plane passing between meeting faces defined by each of said halves, each of said halves having a groove of arcuate cross section extending along said meeting faces transversely of the axis of said body member to define a channel for receiving said polished rod, and a pair of clamping bolts interengaging said halves, said bolts being disposed on opposite sides of said grooves and closely adjacent thereto.

4. In a carrier bar for polished rods, a body member carrying cylindrical trunnion members extending axially outward from said body member in opposite directions, said body member being formed as complementary halves separable along meeting faces defined by each of said halves, each of said halves having a groove extended along said meeting faces transversely of the axis of said body member to define a channel for receiving said polished rod, and means for drawing said halves together along said meeting faces to clamp said polished rod in said channel.

5. In a carrier bar for polished rods, a pair of complementary members each having a pair of integrally formed semi-cylindrical trunnion portions extending outwardly from said members in opposite directions, said complementary members being adapted to be assembled along meeting faces to define a body carrying a pair of cylindrical trunnions, said meeting faces each being grooved to define a polished rod receiving channel, clamping means for drawing said complementary members together, and means providing for additional movement of said members toward each other after said trunnion portions are brought into engagement with each other to thereby clamp said polished rod in said channel.

6. The combination with a polished rod of a gripping member therefor comprising a pair of complementary members adapted to be placed on opposite sides of said polished rod, a pair of clamping bolts positions on opposite sides of said polished rod and inter-engaging said members for drawing said members toward each other to clamp said polished rod therebetween, and means on at least one of said members disposed on opposite sides of said polished rod and spaced therefrom in a position to engage the other of said members when said polished rod is clamped therebetween.

7. In a deep well pumping device including an oscillating driving member, the combination of: a polished rod; and a gripping member comprising a pair of complementary members adapted to be placed on opposite sides of said polished rod, a pair of clamping bolts positioned on opposite sides of said polished rod and interengaging said members for drawing said members toward each other to clamp said polished rod therebetween, means on at least one of said members disposed on opposite sides of said polished rod and spaced therefrom in a position to engage the other of said members when said polished rod is clamped therebetween, and means on said gripping member providing for connection of said gripping member to said oscillating driving means.

8. A gripping member for polished rods comprising a pair of complementary members adapted to be assembled along meeting faces to define a body member, said meeting faces each being grooved substantially midway between the ends thereof to define a polished rod receiving channel, clamping means for drawing said complementary members together, and means on at least one of said members disposed at opposite ends of said meeting faces to engage the other of said members and arrest movement of the ends of said members before said meeting faces are brought into engagement with each other. 9. In a carrier bar for polished rods, a body member having a pair of trunnions formed integrally therewith and extending outwardly therefrom in opposite directions, said body member comprising a pair of complementary halves adapted to be positioned on opposite sides of a polished rod, clamping means for drawing said halves toward each other to clamp said polished rod therebetween, and means on at least one of said halves disposed near the ends thereof in a position to engage the other of said halves when said polished rod is clamped therebetween.

10. In a gripping member for polished rods,

a body member comprising a pair of complementary halves separable along meeting faces defined by each of said halves, each of said halves having a groove extended along said meeting faces transversely of the axis of said body member to define a channel for receiving said polished rod, and a, pair of headed clamping bolts interengaging said halves, said bolts being disposed on opposite sides of said grooves and closely adjacent thereto, each of said bolts being passed freely through an aperture in one of said halves and threadedly engaging another of said halves, the head of one of said bolts engaging the outer surface of one of said halves and the head of the other of said bolts engaging the outer surface of the other of said halves.

JAMES P. RA'I'IGAM 

